Lattice-Matched Ta<sub>3</sub>N<sub>5</sub>/Nb<sub>5</sub>N<sub>6</sub> Interface Enables a Bulk Charge Separation Efficiency of Close to 100%
The interface between the semiconductor light absorber and the metal electrode is critical for facilitating the extraction of photogenerated charges in photoelectrodes. Achieving a lattice-matched semiconductor/electrode interface with low defect density is highly desirable but remains a challenge for Ta3N5 photoanodes. In this study, we synthesized niobium nitride thin film electrodes with controllable crystallographic phases to achieve a lattice-matched Ta3N5/Nb5N6 back contact. This results in an enhanced crystallinity of the Ta3N5 film and reduced interfacial defect density. Consequently, the photoanode with the lattice-matched back contact attains a record half-cell solar-to-hydrogen conversion efficiency of 4.1%, attributed to the bulk carrier separation efficiency of nearly 100%. This work highlights lattice-matching as an effective strategy to enhance the efficiency of thin film-based solar energy conversion devices.
Authors
- Chao Feng (ORCID: https://orcid.org/0000-0002-4434-6551)
- Iztok Arčon (ORCID: https://orcid.org/0000-0003-4333-4054)
- Andraž Mavrič (ORCID: https://orcid.org/0000-0003-2017-9880)
- Matjaž Valant (ORCID: https://orcid.org/0000-0003-4842-5676)
- Gregor Kapun (ORCID: https://orcid.org/0000-0003-0007-4678)
- Tingxi Chen (ORCID: https://orcid.org/0009-0006-7349-9078)
- Beibei Zhang (ORCID: https://orcid.org/0009-0009-6889-3291)
- Yanbo Li (ORCID: https://orcid.org/0000-0002-3017-762X)
- Ronghua Li (ORCID: https://orcid.org/0000-0002-5860-7169)
- Yitong Liu (ORCID: https://orcid.org/0000-0003-0728-3018)
- Zeyu Fan (ORCID: https://orcid.org/0009-0004-2431-6285)
- Yanning Zhang (ORCID: https://orcid.org/0000-0002-3839-2965)
- Zemin Zhang (ORCID: https://orcid.org/0000-0001-8293-391X)
Institutions
- University of Electronic Science and Technology of China (CN)
- University of Nova Gorica (SI)
- Jožef Stefan Institute (SI)
- National Institute of Chemistry (SI)
- Lanzhou University (CN)
Publication Details
- Journal
- ACS Energy Letters
- Published
- 2025-03-27
- DOI
- https://doi.org/10.1021/acsenergylett.5c00603
- Citations
- 3
- Primary Topic
- Advanced Photocatalysis Techniques
- Type
- article
- Field-Weighted Citation Impact
- 1.09
Funders
- National Natural Science Foundation of China
- Javna Agencija za Raziskovalno Dejavnost RS
- National Key Research and Development Program of China